Ness denies the murder of Mr Brown, who was shot dead on July 3, the attempted murder of PC David Rathband, one charge of conspiracy to murder, one charge of possession of a firearm with intent to endanger life, and one of robbing a fish shop.

He was waiting nearby in a white transit van as Moat shot the karate instructor, then shot Ms Stobbart and left her fighting for her life, Robert Smith QC told the jury.

Ness and Moat exchanged a series of text messages as the killer lurked with a loaded shotgun and a bag of ammunition beneath the living room bay window of a house in Scafell, Gateshead.

Ms Stobbart and Mr Brown were inside, having been out for the evening at a local pub.

Moat had told Ms Stobbart he wanted to meet to have "a straightener" with Mr Brown, telephoning her to say: "Okay, I know he’s not a police officer.

"I know he teaches karate in Pelton and Birtley and if I don’t see him today I’ll just come down his lessons."

In the text messages, Moat described to Ness hearing the couple talking about him as he lay in wait beneath the open window.

The first message, sent by Ness to Moat at 01.07am, said: "We will all miss you mate, if it goes down."

At 01.23am Moat replied: "On (sic) problem mate, you’re the best."

At 01.32am Moat texted: "Sam says can you ring her Mam. They are all in this house and I’m in the garden.

"Slagging me off nice and proper.

"Just watch, Rock.

"Say I’m at yours and you’re at a garage."

At 02.03am Moat texted: "Getting bored waiting. they are all just slagging me off. My suffering is so funny apparently.

"I’m going to kick off nice and proper when they come out. Then we’ll see who’s laughing.

"I’m gutted it’s come to this.

"Six years, mate.

"It’s hard to listen to this coming from Sam."

At 02.22am he texted: "They have just opened the window so I’m tempted to lean in but I don’t know if it will open or not.

"What do you reckon, chance it or not?"

At 02.27am he texted: "I’ll make it to the car if I do."

Mr Smith told the court: "These messages made it clear that Raoul Moat was considering leaning into the house through the open window and shooting Chris Brown.

"In the course of police interviews Karl Ness accepted he was aware from the messages that this was Moat’s intention."

At just after 02.30am Mr Brown and Ms Stobbart left the house.

The karate instructor stepped in front of Ms Stobbart as Moat loaded the shotgun then fired.

The first shot hit Mr Brown in the chest. A second shot, which hit his neck, knocked him to the ground.

A third shot killed him.

Mr Smith said: "Moat approached Chris Brown, reloaded the gun and shot him from close range in the head.

"It was a calmly delivered execution."

The killer then turned the gun on Ms Stobbart.

She had run indoors for protection and watched from the front window as Moat killed her boyfriend.

He blasted her through the glass, the shot passed through her arm and into her body where it caused life-threatening injuries.

Moat, carrying the shotgun, then ran from the scene.

Ness meanwhile drove to Albion Road in Byker, Newcastle, where he dumped the Transit van.

He then contacted Awan by telephone and asked to be picked up from Byker.

The trial, which could last five weeks, continues.

RAOUL Moat’s murderous rage was triggered by the breakdown of his six-year-relationship with sweetheart Samantha Stobbart.

The 22-year-old contacted the killer while he was in prison to say she wanted to end the relationship.

She had begun seeing karate instructor Chris Brown, 29, after meeting the self defence expert when he was canvassing for recruits to classes he ran at Birtley Leisure Centre.

But she told Moat she was seeing a Northumbria Police officer, in the hope this would ward off trouble when he was freed from jail, for assaulting a child.

Instead, Moat became obsessed by the fact his ex was seeing another man, and was bent on revenge.

He enlisted the help of his former business partner, Karl Ness, 26, to track down the new man in Samantha’s life, the trial at Newcastle Crown Court heard.

Ness "staked out" Ms Stobbart’s house and used Moat’s Facebook account to trawl for information, the court heard.

He was there when Moat searched the internet for a karate instructor living or working near Ms Stobbart, and when calls were made to leisure centres running karate classes, the jury heard.

Ms Stobbart had seen Moat’s jailing as an opportunity to end their relationship permanently, prosecutor Robert Smith QC told the court.

They split up but the steroid-addicted former doorman had been "persistent in trying to restore the relationship".

"During their time together, Moat was a violent and possessive man and that attention was to continue after Sam Stobbart had left him," Mr Smith said.

"His resentment smouldered while he was in custody, fuelled by the suspicion that Sam Stobbart had met another man.

"Moat’s enduring resentment continued to develop, so much so that he formulated a plan to kill the man he suspected Sam Stobbart was by then involved with. He didn’t know who the man was or where he lived, but he discovered the man was a martial arts instructor."

Moat wrongly believed his rival was a police officer because Ms Stobbart had told him that. She knew ``Chris Brown could expect trouble" when her ex was released, Mr Smith said, and hoped the lie would warn him off.